PelHeat - Biomass Pellets

[PelHeat]

Hello Everyone!

My name is Christopher Scott; I’m a director with a UK company called PelHeat. We are developing a small-scale mobile pellet production unit, and therefore I research different uses for biomass pellets.

After watching Ben’s videos on gasification, it got me really interested in gasification applications, and particularly how pellets are ideal for the process. I still only have a basic understanding of gasification, but definitely see its potential.

Once the development of our first mobile pelletizer is done, I hope to build my own small-scale gasifier to learn the process, and to test several application ideas I’ve got. I will be asking questions on gasification and like wise if people have any question on pellets I’ll try to answer them.

Thanks

Chris

[ben]

Pelletizing is definitely the way to use the widest variety of biomass feedstocks and make them usable by gasifiers, but I think cost has been a factor in people not doing their own pelletizing. What sort of price point will your mobile pelletizer be in?

Could you write a blog post on Victory about the process of pelletizing for people that may not know? Moisture content, hammer mills, pellet density, BTU range and the like.

To write a blog, just go to the bottom of the blogs and click "add blog post" then start writing. You can enter code as well. Your post will go to the front page just like mine. This goes for anyone with something interesting to say. Post it so we can all learn more.

Regards,

Ben

[PelHeat]

Hi Ben,

We are still in the development stage, so currently I cannot give any prices. The units can be towed by the average hatchback/saloon and is powered by its own onboard Perkins diesel engine, which can also operate on bio-diesel under warranty. The mobile nature of the product does mean it is suitable for a group purchase.

I have already set up a blog at www.pelheatblog.com

Regards

Chris

[Andrew Schofield]

Hi Chris,

One gasifier I use needs 1 1/2" cubes cut and split from wood. 40kwe.
Do you have a selection of dies to make briquettes this size? A briquette that is cylindrical is OK.

How critical is feedstock moisture-content?

Andy Schofield
GL-RFSystems

[PelHeat]

Hi Andy

Our machine is designed to make 6mm or 8mm pellets, i.e. the same size that is used in pellet stoves and boilers.

Moisture content in pellet or briquette production is the one of the critical factors for success. Generally for wood the moisture content needs to be between 10-15%, I normally find that 13-15% produces the best quality pellets. Each material is slightly different though, and the percentages will change slightly.

Regards

Chris

[Andrew Schofield]

Hi Chris,

Pellets this size would ge great for a gasifier in the ~2 kwe size range. Do you have a gasifier design?

Andy
GL-RFSystems

[PelHeat]

Hi Andy

We are still in the development stage for our mobile pelletizer, we should have a finished product in the next few months, which will go through field-testing and then we will go into production.

I’ve only just got into gasification, but once I have the time I do want to build my own unit to produce heat and electricity and to test how different pellets made from different materials perform in it.

Regards

Chris

[Dan Wales]

Hi Chris,

I have just joined Victorygasworks and live in Wales. It is good to know that someone is getting together a pellitiser. I have just got into gasification and am looking at the DIY aspect of scrubbing the producer gas using a small water pump so that elctricity can be made and generators kpt clean. I know a small bit about hydraulic action using pressure on beechwood sawdust to make pellets. Does your outfit help make pellets out of woodchips by any chance?

Dan Craver
Ty Coed
Cwm Cych
SA38 9RR

[PelHeat]

Hi Dan,

Yes the machine can make pellets from woodchip, but the machine cannot dry material. And requires material with a moisture content between 13-15% to make the best pellets. Please visit www.pelheat.com and www.pelheatblog.com to find out more.

Dan Wales said:

Hi Chris,

I have just joined Victorygasworks and live in Wales. It is good to know that someone is getting together a pellitiser. I have just got into gasification and am looking at the DIY aspect of scrubbing the producer gas using a small water pump so that elctricity can be made and generators kpt clean. I know a small bit about hydraulic action using pressure on beechwood sawdust to make pellets. Does your outfit help make pellets out of woodchips by any chance?

Dan Craver
Ty Coed
Cwm Cych
SA38 9RR

[PelHeat]

Hi Dutch John

Yes, keeping pellets away from moisture is very important. However in terms of pellets not being suitable for gasifiers, this may depend on the design of the unit. I’m currently sharing information with Community Power Corporation who produce the BioMax gasifiers and they state the unit works very well with biomass pellets.

Here is their website www.gocpc.com

Dutch John said:

Andy,

In Vesa's book is a pellet gasifier explained. But pellets can never be a substitute for wood. That's because they are too small and tend to decompose in the fuel bin by the very bit of moist that is present. You always need to empty the bin after use. Pressure drop over the gasifier is larger. Large gasifiers cannot operate on pellets because of the small size of the fuel.
I don't mean to discourage people, but this is the experience of someone who has driven on woodgas for over 15 years..... Not me, but Vesa Mikkonen.

Regards,
DJ

Andrew Schofield said:

Hi Chris,

One gasifier I use needs 1 1/2" cubes cut and split from wood. 40kwe.
Do you have a selection of dies to make briquettes this size? A briquette that is cylindrical is OK.

How critical is feedstock moisture-content?

Andy Schofield
GL-RFSystems

[jake]

Hi Chris

From working on a gasifier that ran on pellets i can honestly say they perform differently with pellets

This is due to how they decompose when blasted with air.

They tend to expand and then block up when they are hit with the air. The problem lies in the fact that a gasifier needs to have gaps between the fuel to keep the flow of gas at a high velocity. Most wood with break along its structural lines in the wood matrix and will therefore usually break down into roughly the same small charcoal bits. This is why it is better to use larger wood block there are more uncut segments that will break down to a size that will still let the gas through the bed. Pellets have already had there structural lines broken so they will basically break down to fine dust almost. One possible solution is to char the pellets almost fusing them together but you still end up with small bits.

What i have seen with a downdraft gasifier in stationary mode is that you need to shake the grate a lot because it clogs and this means you aren't using the wood to its full. If there are wood chips they are better gasified instead of turned into pellets.

Cheers Jake Martin

ben said:

Pelletizing is definitely the way to use the widest variety of biomass feedstocks and make them usable by gasifiers, but I think cost has been a factor in people not doing their own pelletizing. What sort of price point will your mobile pelletizer be in?

Could you write a blog post on Victory about the process of pelletizing for people that may not know? Moisture content, hammer mills, pellet density, BTU range and the like.

To write a blog, just go to the bottom of the blogs and click "add blog post" then start writing. You can enter code as well. Your post will go to the front page just like mine. This goes for anyone with something interesting to say. Post it so we can all learn more.

Regards,

Ben

[Andrew Schofield]

Dutch John,

I have a friend who uses a machine built in Germany to utilize the sawdust he creates as a byproduct from his hardwood flooring mill. The stock utilized to make the flooring has been kiln dried to a precise degree.

The product made from the sawdust is a brick-like chunk that measures 5 cm x 7cm x 15 cm.

This sawdust is forced at high-pressure through a steel die to melt lignin in the wood by friction. Lignin acts as the particle-binder as the finished brick cools. Any free-moisture will destroy the particle bonding-power to a degree, because the water turns to steam, and forces the particles back-apart. when the die-pressure is removed.

When my friend first began production, there was a problem of the bricks becoming a small pile of burning sawdust.

The problem of disintegration while burning is solved in that product. I observed, and poked at these bricks burning in a traditional parlor-stove designed for split-firewood.

While these bricks are certainly too-large for my gasifiers (saw them into smaller chunks?), and 8mm pellets are too-small, I hope an optomum size can be produced one day.

Andrew Schofield


Dutch John said:

Andy,

In Vesa's book is a pellet gasifier explained. But pellets can never be a substitute for wood. That's because they are too small and tend to decompose in the fuel bin by the very bit of moist that is present. You always need to empty the bin after use. Pressure drop over the gasifier is larger. Large gasifiers cannot operate on pellets because of the small size of the fuel.
I don't mean to discourage people, but this is the experience of someone who has driven on woodgas for over 15 years..... Not me, but Vesa Mikkonen.

Regards,
DJ

Andrew Schofield said:

Hi Chris,

One gasifier I use needs 1 1/2" cubes cut and split from wood. 40kwe.
Do you have a selection of dies to make briquettes this size? A briquette that is cylindrical is OK.

How critical is feedstock moisture-content?

Andy Schofield
GL-RFSystems

[Andrew Schofield]

Hoi John,

You could probably use a sharp mackinaw axe with a mighty round-house (boiler-maker) whack.
Those are Eco-Heating brand. http://www.sawmillbill.com/

How do the sparkplugs look? Gasoline is so touchy.

Andrew